Vacuum evacuation of a container may be used to preserve freshness of food or other perishables within an interior of the container. Vacuum evacuation is typically achieved by applying a source of vacuum to the container. However, the container may become deformed by ambient pressure when evacuated, and deformation of the container may be especially problematic for containers that have flexible sidewalls. Interior surfaces of the flexible sidewalls may be forced into contact with one another, and may form seals therebetween that isolate a portion of the interior of the container from the source of the vacuum.
A pouch for vacuum packaging items has a first panel and a second panel that define an interior volume and an opening. Air evacuation channels are embossed onto inner surfaces of one or both of the first and second panels. The pouch has a divider panel disposed between the first and second panels to form distinct interior sub-volumes on either side of the divider panel. The distinct sub-volumes may be evacuated individually and allow the pouch to separately hold two items and keep the items separated. The divider panel may also have one or both sides thereof embossed with evacuation channels.
A flexible storage bag has first and second sidewalls defining an internal volume that can be accessed from an open edge. First and second interlocking closure strips are attached across the open edge to internal surfaces of the first and second sidewalls. A one-way valve element is attached to the first sidewall and includes a base layer having an aperture communicating with a hole in the first sidewall. A top layer is adhered to the base layer by two parallel strips of adhesive on opposite sides of the base layer such that the top layer covers the aperture in the base layer. The valve element is made of flexible thermoplastic film and is located proximate to a corner formed by a first side edge and the open edge. In addition, a viscous material, such as oil, grease, or a lubricant, is disposed between the base and the top layers, in order to prevent air from reentering the bag. When a vacuum is applied to the valve element or the bag is forcibly compressed, air passes through the hole in the first sidewall and the aperture in the base layer, thereby partially displacing the top layer from the base layer. The air passes to the environment along a channel formed by the adhesive strips. Another similar flexible storage bag has a plurality of protruding, elongated ridges extending from an inner surface of one of the sidewalls. At least one of the ridges includes a plurality of notches formed therein to provide a plurality of ridge segments for the flow of air.
A vacuum packaging bag has a resealable inner seal, such as a peel seal, that separates an internal volume of the bag into a storage section and a closure section. A resealable closure mechanism, such as a pair of opposing interlocking zipper profiles, is disposed in the closure section and a check valve is disposed through a side wall of the bag. A strip of textured material is disposed opposite to the check valve to provide a communication passage for the removal of liquids and gases through the valve. A vacuum system engages the check valve to evacuate the pouch.
Addition of flow channels to interior surfaces of a pouch may typically add complexity and cost to the manufacture of the pouch, and may restrict the utility of a production line to the manufacture of pouches that include flow channels.